The present invention relates to a luminous multiple glazing unit and more particular to a luminous multiple glazing unit comprising light-emitting diodes.
Light-emitting diodes or LEDs were originally employed as status or indicator lights in electrical and electronic appliances but have already, for a number of years, been used as light sources in signaling devices such as traffic lights, in automotive vehicle lighting (indicators, side lights) or in torches or path lighting. Light-emitting diodes are advantageous because of their long lifetime, their luminous efficiency, their robustness and their compactness, making systems using them more durable and easier to maintain.
Document DE 10 322 561 describes an insulating double glazing unit, for illuminating the façades of buildings, comprising (in the embodiment corresponding to FIG. 4 in this document DE 10 322 561):                a first glazing pane with internal and external faces;        a second glazing pane with main internal and external faces, placed opposite the first glazing pane;        an internal space filled with gas;        a peripheral seal;        a peripheral frame made of aluminum, located between the two glazing panes, forming a spacer and making contact with the sealing means, this frame bearing two groups of diodes, respectively on two opposed edges of the glazing unit, the diodes being fixed to mountings that lie perpendicular to the main faces of the glazing panes;        a reflector for each group of diodes, forming an extension of the frame, the reflectors being arranged to redirect light traveling toward the internal face of the second glazing pane toward the internal face of the first glazing pane; and        the light then being reflected or deviated by the internal face or faces and/or by one or more coatings on the internal or external faces.        
The Applicant has observed that this light-emitting-diode-comprising insulating glazing unit is not optimized in terms of optical performance.